1. Field of the Invention
The present invention relates to an elevator control apparatus which controls a motor that allows an elevator to move downward and upward and a motor that allows a door to be opened and closed with a microcomputer.
2. Description of the Related Art
The configuration of a common elevator apparatus is shown in FIG. 5. In FIG. 5, reference numeral 1 denotes a counter weight, 2 denotes a deflector sheave, 3 denotes a traction machine, 6 denotes a motor for moving a car downward and upward, 7 denotes an elevator rope, 8 denotes a door drive control apparatus, 9 denotes an elevator car, 10 denotes an elevator door, and 11 denotes a cable for connecting an elevator drive control apparatus 12, the door drive control apparatus 8, an operation panel inside the car, and lights inside the car, etc. FIG. 6 is a detailed view of the door 10 portion of the elevator. In FIG. 6, reference numeral 13 denotes a motor for opening and closing a door, 14 denotes a pulley for driving a link mechanism 15, 17 denotes a hanger roller for guiding the door 16, 18 denotes a hanger case, and 18A denotes a detection plate for actuating a door completely open detector OLT 18B and a door completely closed detector CLT 18C. In an elevator configured as described above, the elevator drive control apparatus 12 has previously been controlled by a commonly used microcomputer, as described in "Application of VVVF Control to an Elevator" (Mitsubishi Electric Technical Report, Vol. 58, No. 12, 1984, pp 20 to 24). However, the door drive control apparatus 8 is generally formed by an analog circuit. For this reason, connection signals among respective control apparatus are limited. For example, as shown in FIG. 7, at the very most, a door open instruction DOI, a door close instruction DCI, a running (moving downward and upward) signal RU are sent out from the elevator drive control apparatus 12 to the door drive control apparatus 8, and a door completely open signal DOS indicating that a door is open, a door completely closed signal DCS indicating that a door is closed, an emergency door reverse signal EDR indicating that a safety device for the door has been actuated are sent out from the door drive control apparatus 8 to the elevator drive control apparatus 12. In FIG. 7, reference numeral 6A denotes an encoder for detecting the speed of the elevator motor 6 and the position of the car 9, 13A denotes an encoder for detecting the speed of a motor 13 for driving a door and the position of the door. In such an elevator system, checking of an abnormality of the door drive control apparatus 8 is performed simply, in such a way that time period Tc, from the time a door close instruction DCI from the elevator drive control apparatus 12 to the door drive control apparatus 8 is output to the time a door completely closed signal DCS is sent back, is checked, or time period T.sub.0, from when a door open instruction DOI is output to when a door completely open signal DOS is sent back, is checked. The abnormality is detected and processed by the elevator drive control apparatus 12 based on the above check.
In the above-described conventional elevator control apparatus, since the door drive control apparatus 8 is not equipped with a means for checking a door open/close abnormality, the checking of an abnormality related to a door can be performed only by the elevator drive control apparatus 12. For this reason, when the check mechanism of the elevator drive control apparatus 12 is abnormal, the restart sequence of the door open/close for itself will be performed by the abnormal elevator drive control apparatus 12 itself. As a result, there is a mode in which it is difficult to operate the restart sequence normally, or there exists a problem in that the safety check cannot be performed for the whole elevator control apparatus.